Electric-arc lamp.



No. 697,077. Patented Apr. 8, |902.

' J. EBERHARDT.

ELEcTmc Anc LAMP.

(Application lsd Aug. 18.- 1901.?

(lo llndel.)

' \4 |NvENTOR f ATTORNEY UNTTED STATES PATENT OFFICE.

JOHN EBERHARDT, OF CHICAGO, lLLlNOlS.

ELECTRlC-ARC LAM P,

SFECIFLCATIN forming part of Leiters Patent No. 697,077', dated Ap 8,1902.

Application iled August 13,1901. Serial Nol 71,897. (No model.)

fo if/Z wiz/om zit may concern:

Beitkuowuthat I, JOHN EBERHARDT, a citi- Zen ofthe United States,residing at Chicago, in the county ot Cook and State of Illinois, haveinvented certain new and useful Improvements in Arc-Lamps, of which thefollowing is a full, clear, and Xact description.

This invention relates to electric-arc lamps, and has referenceespecially to clutches by means of which the feeding of the upper-carbonelectrode is controlled.

The object of the invention is to provide a clutch which will hold thecarbon at its proper position regardless of shocks or jarring to whichthe lamp may be subjected while in use, thus especially adapting it fora lamp located on a car or train-as, for instance, a headlight.

A further object is that the clutch shall be sensitive to variations inthe length of the arc and will tend to maintain the same at a constantcandle-power.

My improved clutch consists of the details of construction andcombinations hereinafter described and claimed.

In the accompanying drawings, Figure l is a side elevation of theclutch, showing its position when the lamp is not burning. Fig. 2 is asimilar view showing the position of the parts when the are is firstestablished. Fig. 3 is a rear elevation of the clutch and a portion ofthe vertical standard by which it is guided.

Similar letters indicate like parts in each View.

The carbon electrode is indicated by a. It passes through a guiding-ringI), fixed horizontally to the lower end of a vertical standard c,forming a part of the lamp-frame. Above the ring b is the clutch-frameCZ, loosely encircling the rod d. d. represents a roller adapted to rollagainst the iiat'surtace of the lower end of the standard c to reducefriction in the movements oi the clutch.

(Z2 is a screw passing through the clutchframe and adapted to impingeagainst the lug di on the standard c andlimit the upward movement of theclutch. Opposite the roller the frame d is split to form ears, betweenwhich is pivoted a dog c, having a gripping edge e. The frame d isprovided with the lugs di, adapted to strike upon the upper side of thefixed ring b. To the outer end of the dog is freely attached a rod f,through which the clutch is operated.

d5 represents a guiding-screw for the carbon cz.

lt is not considered necessary to show the usual electromagnet orsolenoid which actuates the clutch, it being understood that the rodf israised or lowered by such a regulating magnet or solenoid as is commonlyused.

In explaining the operation of the clutch it may be assumed that whenthe lamp is not burning the upper carbon a is resting upon the lowercarbon. When the current is turned on, the regulating-magnet raises therod f, causing the edge e of the dog c to bear against the side of thecarbon and clamp it against the guided, Further movement of the rodf isaccompanied by the carbon and continues until stopped bythe screw d2coming into contact with the lug d3. In this upward movement to strikethe arc the traverse of the carbon is in a perfectly vertical line, andno binding can take place because of the action ofthe roller d. As thearc settles down to its normal burning length the clutch lowers to anintermediate position between those shown in Figs. l and 2. As thecarbon consumes the clutch gradually lowers until the lugs di strike theringb, and the edge e/ is released from the carbon by the furtherdownward movement of the rod f. XVhen the carbon is thus released, itfeeds by gravity until again gripped and held by the dog actuated by thecontrolling-magnet.

The location of the roller back of the standard makes every movementofthe clutch positive and exact, there being no loose joints or openplaces which might permit of the carbon working loose from the clutch incase the lamp is subjected to jarring or shocks.

In the case of cluches heretofore used in this kind of service muchdifficulty has been encountered because of slight variations in thediameter or" the various carbons, the smallest departure of this naturefrom the standard size for which the clutch is made resulting inirregular 'feeding of the carbon. A variation of more than one-sixteenthof an inch, however, is seldom,if ever, met, and this my improved clutchtakes care of without liability to faulty feeding, as will be readilyunderstood from the foregoing description.

This clutch also dispenses with all springs, the care necessary inkeeping them in adjustment, extra parts required for their operation,dac.

Havingr described my invention, I claim- 1. A clutch for arc-lamps,consisting of a frame carryinga pivoted gripping-dog on one side, and aroller on the opposite side, in combination with a stationary part,against which said roller bears and which is located between the rollerand the opening in the frame, substantially as described.

2. A clutch for arc-lamps, consisting of the combination of a frameprovided with tvrip- 15 ping-lugs d4,a dog e pivoted thereto,a roller dcarried by said frame, the standard c against which said roller bears,anda support against which the lugs d4 are adapted' to strike.

In witness whereof I subscribe my signazo ture in presence of twowitnesses. Y

JOHN EBERHARDT.

Witnesses:

E. S. CLEARY, R. C. VILAs.

